Hi!
1) Supouse I don't want reordering, so in 'tc' I don't add reorder
option. Will this code work? The previous (on this subject) patch has
a the following:
+ /* for compatiablity with earlier versions.
+ * if gap is set, need to assume 100% probablity
+ */
+ q->reorder = ~0;
+
Should it be set to 100% or 101%?
This "q->reorder = ~0;" mean 100%?
2) If I set latency = 50ms and a jitter = 300ms, tabledist can give me
a negative number. This value is addes to cb->time_to_send, so it
could change it to a negative value. Should we only accept positives
number before add it to cb->time_to_send? or will
q->qdisc->enqueue(skb, q->qdisc) put the package on the queue in a
special way so it will be handled "before" other packages alrealy on
the queue but with gretaer time_to_send?
Regards,
Julio
On 5/23/05, Stephen Hemminger <shemminger@xxxxxxxx> wrote:
> Thanks, Julio you spotted the problem with the logic. This should fix it:
>
> Index: netem-2.6.12-rc4/net/sched/sch_netem.c
> ===================================================================
> --- netem-2.6.12-rc4.orig/net/sched/sch_netem.c
> +++ netem-2.6.12-rc4/net/sched/sch_netem.c
> @@ -181,13 +181,9 @@ static int netem_enqueue(struct sk_buff
> q->duplicate = dupsave;
> }
>
> - /*
> - * Do re-ordering by putting one out of N packets at the front
> - * of the queue.
> - * gap == 0 is special case for no-reordering.
> - */
> - if (q->gap == 0 && q->counter < q->gap &&
> - q->reorder < get_crandom(&q->reorder_cor)) {
> + if (q->gap == 0 /* not doing reordering */
> + || q->counter < q->gap /* inside last reordering gap */
> + || q->reorder < get_crandom(&q->reorder_cor)) {
> psched_time_t now;
> PSCHED_GET_TIME(now);
> PSCHED_TADD2(now, tabledist(q->latency, q->jitter,
> @@ -196,6 +192,10 @@ static int netem_enqueue(struct sk_buff
> ++q->counter;
> ret = q->qdisc->enqueue(skb, q->qdisc);
> } else {
> + /*
> + * Do re-ordering by putting one out of N packets at the front
> + * of the queue.
> + */
> PSCHED_GET_TIME(cb->time_to_send);
> q->counter = 0;
> ret = q->qdisc->ops->requeue(skb, q->qdisc);
>
--
----------------------------
Julio Kriger
mailto:juliokriger@xxxxxxxxx
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